Device for expanding collapsed casings



7 "ff-" 1930. c. LANGSTAFF DEVICE FOR EXPANDING -COLLAPSED CASINGS FiledAug. 15, 1928 Patented July 1, 1930 mnrsn "STATE-s;

PATENT QFFICE crmro'na. LANGSTAFE, or HAWTHORNE, oamronmn, ASSIGNQR oroxen-minim To FRED A. rommn Ann ONE-THIRD. T0 wr LrAM e. WHALEX, BOTHor: nos AN- GELES, CALIFORNIA;

DEVICE .ron EXPANDING. ooLLArsnn oAsINes.

Application filed August 15, 1928. Serial No. 299,692;

This inventionrelates to an expander tool for expanding casing in a deepwell which has collapsed due to a' high externalpr'essure. The generalobject of the invention is to provide a device of simple construction.for effecting this operation.

A further object of the invention is to provide a device of this kindwhich will operate in such a way that the rotary move ment of the. toolstring carrying the expander tool will operate to effect the expandingof the casing.

Further objects of the invention will appear hereinafter.

The invention consists in the novel parts P and combinations of partstobe described hereinafter, all of which contribute to produce aneflicient device for expanding col lapsed casing. y

A preferred embodiment of the invention is described in the followingspecification, while the broad scope of the invention is pointed outinthe appended claims.

In the drawings:

Figure 1 is a side elevation of the expanding device embodying myinvention, and showing a short portion of a collapsed casing incross-section to indicate how the device operates in practice.

Figure 2 is a vertical section through the expander device shown inFigure 1, and in dicating the expander tools or arms in their collapsedor folded condition in full lines, and illustrating the expander toolsor arms in dotted lines in their expanded condition.

Figure 3: is a cross-section taken through the device on the line 3'3 ofFigure 2.

' Figure 4- is a cross-section on the line 44; of Figure 2.

Figure 5 is a cross-section on the line 5--5 of; Figure 2.

The device includes in its construction a head 1 which isprovided withmeans, such as a tapered pin 2", for attaching the same at the lower endof the tool string. Below the head I provide a swivel collar 3 to whichis attached a plurality of movable expander tools or dogs- 4. These dogsare attached in any suitable manner to enable them to move outwardly ina substantially radial plane. In the present instance, each dog isin'the form of an arm, preferablyar-ranged in pairs and mounted teexten-dl longitudinally with the longitudinal axis of the head 1 andeach dog is'attached at its upper end to the under side of the collar bya pivot pin 5. In order to attach these dogs 4, the under side of thecollar 3 is provided with a slot 6 corresponding toeach dog, and the dogis formed with atongue 7 that projects up into this slot so that theattaching pins 5 can be driven through the wall ofthe collar in ahorizontal plane, being received in drilled openings 8- forthis purose.

In the operation of the tool, the dogs 4 engage the inner wall of acollapsed, casing, such as the casing 9 illustrated in Figure. 1. Whenthe dogs engage the wall of the casing, the casing operates to hold thedogs and the collar 3 against rotation; The tool is constructed so thatwhen this occurs, the

- continued rotation of the head 1 onits longitudinal axis will causethe dogs 4 to-mQve outwardly in succession and expand the collapsed partIO of the casing,

in order to accomplish this, I prefer to provide the lower ends of thedogs; with tapered noses 11 respectively, thatis to say,

each'dog presents an inclined face- 12,, which Ian 3- in place, at thesame time permitting it:

to swivel freelyon thelongitudinal'faxils'iof the head. i

The lower portion of the mandrel. provided with cain means for engagingthe inner sides of? the expander tools; 4; to expand them. This cammeans is preferably the form of two sets of cams, located in differentplanes of rotation, and includingan upper set consisting of twooppositely-disposed cams 17 (see Figure 4:), and a lower set consistingof two oppositely-disposed cams 18 (see Figure 5). The dogs a areoperated in opposite pairs by these cams. The cams 17 will not operatethe dogs l (see Figure 4:), but will actuate the dogs 49. This mode ofoperation is accomplished by providing the dogs 45 with a clearance slot19 on their inner faces, and by also providing the dogs 4: with aclearance slot 20 on their inner faces. With this construction it willbe evident'that when the cams 17 strike the inner faces 21 of the dogs4: they will force the same outwardly. Likewise, when the cams l8 engagethe inner faces of the dogs P these dogs will be moved outwardly.

It will be evident that in the operation of the tool there is'a positionof rest, as illustrated in Figures 4 and 5, in which none of the dogsare in their expanded position. This is the position in which the deviceis lowered down into the casing 9 which is to be expanded. It will beevident that when the noses 11 of the dogs strike the collapsed portion10 of the casing, they will be held against rotation. By rotating thetool string carrying the head 1, the dogs will be swung outwardly inunison, thereby expanding the casing. As this occurs the tool isgradually lowered.

If the dogs happen to slip around on the inside of the casing, thissimply assists in the manipulation of the inner face of the wall, whichwill eventually expand the collapsed zone 10 back to its normal orproper diameter.

The pins 5 are constructed so that some of the pins overlap the othersso as to hold them in place, the last pin driven into place operating asa general key to hold all of the other pins against dislodgment in use.The head and mandrel, and the inner faces of the dogs, are provided witha water bore 22 for carrying circulating water down through the tool ifdesired. 7

Although I have described this invention as applied to an expander forcollapsed casing, it is obvious that the expanding feature of the devicemay be employed in other tools for example, under-reamers and back-offtools.

It is understood that the embodiment of the invention described hereinis only one of the many embodiments this invention may take, and I donot wish to be limited in the practice of the invention, nor in theclaims,

to the particular embodiment set forth.

What I claim is:

V 1. In an expanding device for expanding a collapsed casing in a well,the combination of a head having means for attaching the same to thelower end of a tool string, a

collar having a swivel connection on the longitudinal axis of said head,a plurality of expander dogs attached to the collar toward one end so asto swing out at their other ends in a substantially radial direction,and having tapered noses for engaging the wall of the casing at thecollapsed point, and means carried by the head for moving the expandingdogs outwardly to expand the collapsed casing.

2. In an expanding device for expanding a collapsed casing in a well,the combination of a head having means for attaching the same to thelower end of a tool string, a collar having a swivel connection on thelongitudinal axis of saidhead, a plurality of expander dogs attached tothe collar to ward one end so as to swing outwardly at their other ends,and in substantially radial planes to engage the wall of the collapsedcasing, and operating so that the engagement with the wall of the casingholds the expander dogs and the collar against rotation on the axis ofthe head, and means carried by the head and operating by the rotarymovement of the head relative to the collar to move theexpander dogsoutwardly to expand the collapsed casing;

3. In an expanding device for expanding a collapsed casing in a well,the combination of a head having means for attaching the same to thelower end of a tool string, a collar having a swivel connection on thelongitudinal axis of said head, a plurality of expander dogs pivotallyattached to the collar adjacent their upper end-sand capable of swingingoutwardly in substantially radial planes, said expander dogs havingtapered noses for engaging the Wall of the easing at the collapsed pointand operating to hold the expander dogs and the collar against rotation,and a mandrel attached to the head extending down on the axis of thehead with cam means for engaging the said expander tools when a relativerotary movemtizpt of thehead occurs with regard-s to the co ar.

4:. In an expanding device for expanding a collapsed casing in a well,the combination of a head having means for attaching the same to thelower end of a tool string, a collar having a swivel. connection on thelongitudinal axis of said head, a plurality of expander dogs pivotallyattached to the collar adjacent their upper ends and capable of swingingoutwardly in substantially radial planes with respect to thelongitudinal axis of the head, a mandrel attached to the head andextending downwardly from the same on the axis of the head, saidexpander dogs having tapered noses at their lower ends for engaging thewall of the casing at the collapsed point to hold the expander dogs andthe collar against rotation, said mandrel having cams for engaging theinner sides of the expander tools to move the same outwardly when thesaid head is rotated on its axis relatively to the collar and expanderdogs.

5. In an expanding device for expanding a collapsed casing in a well thecombination of a head having means for attaching the same to the lowerend of a tool spring, a collar having a swivel connection on thelongitudinal axis of said head, a plurality i of dogs disposed inoppositely-located pairs,

' pivotally attached at their upper ends to the day of July under sideof the collar, a mandrel attached to the under side of the head andextending downwardly on the axis of the head, said mandrel having a pairof oppositely-disposed cams for expanding a pair of oppositely-disposeddogs, and having another pair of oppositely-disposed cams for expandinganother pair of oppositely-disposed dog-s, said last-named cams beinglocated in a different plane of rotation from the first-' named cams.

6. In an expanding device for expanding a collapsed casing in a well,the combination of a head having means for attaching the same to thelower end of a tool string, acollar having a swivel connection on thelongitudinal axis of said head, a plurality of expander dogs attached tothe collar toward one end so as to swing out at their other ends in asubstantially radial direction, and having tapered noses for engagingthe wall of the casing at the collapsed point, said tapered nosesoperating when engaging the wall 01": the collapsed casing to. preventrotation of the collar, and means carried by the head for moving theexpanding dogs outwardly to expand the collapsed casing. Signed at LosAngeles, Calif., this 31st 1928. LINTON A. LANGSTAFF.

